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Synchronization in Complex Oscillator Networks and Smart Grids  [PDF]
Florian D?rfler,Michael Chertkov,Francesco Bullo
Mathematics , 2012, DOI: 10.1073/pnas.1212134110
Abstract: The emergence of synchronization in a network of coupled oscillators is a fascinating topic in various scientific disciplines. A coupled oscillator network is characterized by a population of heterogeneous oscillators and a graph describing the interaction among them. It is known that a strongly coupled and sufficiently homogeneous network synchronizes, but the exact threshold from incoherence to synchrony is unknown. Here we present a novel, concise, and closed-form condition for synchronization of the fully nonlinear, non-equilibrium, and dynamic network. Our synchronization condition can be stated elegantly in terms of the network topology and parameters, or equivalently in terms of an intuitive, linear, and static auxiliary system. Our results significantly improve upon the existing conditions advocated thus far, they are provably exact for various interesting network topologies and parameters, they are statistically correct for almost all networks, and they can be applied equally to synchronization phenomena arising in physics and biology as well as in engineered oscillator networks such as electric power networks. We illustrate the validity, the accuracy, and the practical applicability of our results in complex networks scenarios and in smart grid applications.
Smart Grids: A New Framework for Efficient Power Management in Datacenter Networks
Okafor Kennedy C,Udeze Chidiebele. C,E. C. N. Okafor,C. C. Okezie
International Journal of Advanced Computer Sciences and Applications , 2012,
Abstract: The energy demand in the enterprise market segment demands a supply format that accommodates all generation and storage options with active participation by end users in demand response. Basically, with today’s high power computing (HPC), a highly reliable, scalable, and cost effective energy solution that will satisfy power demands and improve environmental sustainability will have a broad acceptance. In a typical enterprise data center, power managment is a major challenge impacting server density and the total cost of ownership (COO). Storage uses a significant fraction of the power budget and there are no widely deployed power-saving solutions for enterprise storage systems. This work presents Data Center Networks (DCNs) for efficient power management in the context of SMART Grids. A SMART DCN is modelled with OPNET 14.5 for Network, Process and Node models. Also, an Extended SMART Integration Module in the context of SMART DCN is shown to be more cost effective than the traditional distribution grid in DCNs. The implementation challenges are discussed also. This paper suggests that smartening the grid for DCN will guarantee a sustainable energy future for the enterprise segments.
Wireless Sensor Networks Based Control Strategies for the Enhancement of Reliability in Smart Grids  [PDF]
A. K. P. Kovendan, D. Sridharan
Circuits and Systems (CS) , 2016, DOI: 10.4236/cs.2016.79216
Abstract: The rapid increase in the demand for electricity necessitates the power quality improvement for achieving better reliability in smart grids. Wireless Sensor Networks (WSN) is the proven technology for reliable monitoring. This paper proposes a system model for the development and implementation of WSN based communication system for the monitoring of distributed generation, loads and transmission lines in the electrical grid and a controller system for automated control on the electrical grid. This work also aims to reduce the carbon footprints by reducing the dependency of electrical grid through the enhancement of distributed generation and grid sharing for avoiding voltage rise problem. To achieve this, a smarter electrical grid has been developed for the validation of smart grid considering a generation substation, a transmission substation and a distributed generation with loads. The occurrence of power quality issue and voltage rise has been controlled by active power control strategy. The communication network and controller has been modeled and tested for the performance of monitoring system and data communication capability on smart grid.
Energy Efficiency and Renewable Energy Technologies Using Smart Grids: Study Case on NIPE Building at UNICAMP Campus  [PDF]
M. D. Berni, P. C. Manduca, S. V. Bajay, J. T. V. Pereira, J. T. Fantinelli
Smart Grid and Renewable Energy (SGRE) , 2014, DOI: 10.4236/sgre.2014.58018
Abstract: In its broadest interpretation, the smart grid vision sees the future of power industry transformed by the introduction of intelligent two-way communications, ubiquitous metering and measurement. This enables much finer control of energy flows and the integration and efficient use of renewable forms of energy, energy efficiency methodologies and technologies, as well as many other advanced technologies, techniques and processes that wouldn’t have been practicable until present. The smart grid vision also enables the creation of more reliable, more robust and more secure power supply infrastructure, and helps optimize the enormous investments required to build and operate the physical infrastructure required. The smart grid promises to revolutionize the electric power business that has been in place for the past 75 years. This work discusses the efficiency, targeted at the consumer units of electricity, with a view to sustainability and potential for technological innovation. The issue is addressed from two perspectives: the systems for generation and power distribution, and the design of a building “smart energy”. Because of the novelty of the subject in our country, the concepts presented and treated throughout this work come from material obtained at events and specialized sites on electric power system in Brazil and worldwide, being accompanied by information and data from NIPE’s building at University of Campinas’s campus case study in which it exemplifies the applicability of the techniques and recommended technologies.
Energy Management and Smart Grids  [PDF]
Rosario Miceli
Energies , 2013, DOI: 10.3390/en6042262
Abstract: The paper outlines energy management concepts and the smart grid evolution. The necessity of considering energy management as a crucial innovation in load supplying to permit a more powerful penetration of renewable energy usage at the building and city level and to perform energy savings and CO2 emissions reduction is pointed out. The driving factors to enhance the current power distribution are presented, and the benefits concerning smart grids are underlined. In the paper, a specific energy management analysis is reported by considering all the electric value chain, and the demand-side management and distributed on site control actions are described. To verify the benefit of energy management control actions, a house simulator and a grid simulator are here presented and the results discussed in three different scenarios. Moreover, in the paper, the evaluation of ecological benefits are reported, and a cost benefit analysis of the energy management system is performed. Results pointed out that with the standard control actions, the system is not economic for the end user, and only by using energy management systems with renewable energy, in site production remunerative energy savings can be reached. Finally the evolution of smart grids is presented, focusing on potential benefits and technical problems. The active grids, microgrids and virtual utility are described, and final consideration on hypothetical scenarios is presented in the conclusion.
Enhancements of G3-PLC Technology for Smart-Home/Building Applications  [PDF]
Luca Di Bert,Salvatore D'Alessandro,Andrea M. Tonello
Journal of Electrical and Computer Engineering , 2013, DOI: 10.1155/2013/746763
Abstract: To enable the smart grid concept, it is fundamental to consider the in-home/building context where, beside the conventional home networking services, home automation and smart energy management services have to be offered. In this paper, we consider the in-home/building scenario, for which we propose a convergent network architecture to enhance the performance of the narrowband power line communication (PLC) G3-PLC technology through its integration with an Ethernet-based network. To this end, we define the protocols characterizing the network modules, namely, switches and routers, which allow for integrating the G3-PLC with Ethernet devices. Since Ethernet represents a convergent standard for many communication devices, by adding this functionality to G3-PLC, interconnectivity with other heterogeneous nodes can be offered. Furthermore, since the G3-PLC medium access control layer is based on a carrier sense multiple access scheme, its performance decreases when the number of network nodes contending for the channel increases. Therefore, we evaluate the network performance when an optimized time division multiple access scheme is adopted. The proposed convergent network architecture has been implemented in the OMNeT++ network simulator. 1. Introduction Energy efficiency and power saving were identified in 2010 as fundamental objectives to contribute to the sustainable growth specified in the “Europe 2020” strategy [1]. As a consequence, in the near future, the power grid needs to become a distributed large-scale system that has to smartly manage flows of electricity produced by big or small plants, that is, a smart grid (SG). To this respect, demand side and demand response mechanisms have to be implemented, so that prosumers will actively collaborate in the use and delivery of energy [2, 3]. To enable the SG concept, it becomes therefore fundamental to consider the in-home/building context where, beside the conventional home networking services—for example, triple play (high speed internet access, television, telephone), infotainment, and resource sharing in local area networks (LANs)—, home automation and smart energy management services have to be offered. Differently from home networking services, home automation and energy management services usually involve a large number of nodes (sensors/actuators) that are pervasively deployed within the house/building and transmit a small amount of data. Despite the small amount of data, strict requirements as coverage, latency, delay, and robustness must be fulfilled for some applications, for example, the
Analyzing Cascading Failures in Smart Grids under Random and Targeted Attacks  [PDF]
Sushmita Ruj,Arindam Pal
Computer Science , 2014,
Abstract: We model smart grids as complex interdependent networks, and study targeted attacks on smart grids for the first time. A smart grid consists of two networks: the power network and the communication network, interconnected by edges. Occurrence of failures (attacks) in one network triggers failures in the other network, and propagates in cascades across the networks. Such cascading failures can result in disintegration of either (or both) of the networks. Earlier works considered only random failures. In practical situations, an attacker is more likely to compromise nodes selectively. We study cascading failures in smart grids, where an attacker selectively compromises the nodes with probabilities proportional to their degrees; high degree nodes are compromised with higher probability. We mathematically analyze the sizes of the giant components of the networks under targeted attacks, and compare the results with the corresponding sizes under random attacks. We show that networks disintegrate faster for targeted attacks compared to random attacks. A targeted attack on a small fraction of high degree nodes disintegrates one or both of the networks, whereas both the networks contain giant components for random attack on the same fraction of nodes.
Performance Analysis of IEEE 802.15.4 Compliant Wireless Devices for Heterogeneous Indoor Home Automation Environments  [PDF]
Juan Antonio Nazabal,Peio López Iturri,Leire Azpilicueta,Francisco Falcone,Carlos Fernández-Valdivielso
International Journal of Antennas and Propagation , 2012, DOI: 10.1155/2012/176383
Abstract: The influence of topology as well as morphology of complex indoor scenarios in the deployment of wireless sensor networks and wireless systems applied to home and building automation systems is analyzed. The existence of loss mechanisms such as material absorption (walls, furniture, etc.) and strong multipath components as well as the increase in the number of wireless sensors within indoor scenarios increases the relevance in the configuration of the heterogeneous wireless systems. Simulation results by means of empirical-based models are compared with an in-house 3D ray launching code as well as measurement results from wireless sensor networks illustrate the strong influence of the indoor scenario in the overall performance. The use of adequate radioplanning strategies lead to optimal wireless network deployments in terms of capacity, quality of service, and reduced power consumption. 1. Introduction The use of wireless sensor networks (WSNs) is growing rapidly into a large number of fields of application [1–3], such as building automation systems (BAS), industrial monitoring [4, 5], farming and agriculture [6–9], structural monitoring [10], civil infrastructure state monitoring [11–13], healthcare monitoring [14, 15], location and guiding [16], or security and defense, among others. The future trend is to increase the number of nodes, in order to increase the interaction with users as well as capturing more information from the surrounding environment. On the other hand, the use of building automation systems, especially oriented to home automation, is growing all over the world [17–22]. As time goes by more homes integrate an automation system for intelligently controlling elements such light, heating, and energy management. The connection between the components of these systems has been made typically via electric conducting cables but nowadays the use of wireless technologies for communication with each other is taking a predominant role. In the case of home and building automation systems, the foreseen scenario is indoor, with high complexity related to the topology as well as the morphology. This leads to increased losses, in terms of material absorption as well as to strong multipath propagation. Future systems will tend to use a large number of sensors, in which energy consumption as well as capacity are key issues to be considered. The application of Building Automation systems to residential environments is also called Smart Home systems. In this way, a Smart Home can be defined as the application of automation and integration systems of
Towards the Smart Grid: Substation Automation Architecture and Technologies  [PDF]
A. Leonardi,K. Mathioudakis,A. Wiesmaier,F. Zeiger
Advances in Electrical Engineering , 2014, DOI: 10.1155/2014/896296
Abstract: This paper deals with Industrial Control Systems (ICS) of the electrical sector and especially on the Smart Grid. This sector has been particularly active at establishing new standards to improve interoperability between all sector players, driven by the liberalization of the market and the introduction of distributed generation of energy. The paper provides a state-of-the-art analysis on architectures, technologies, communication protocols, applications, and information standards mainly focusing on substation automation in the transmission and distribution domain. The analysis shows that there is tremendous effort from the Smart Grid key stakeholders to improve interoperability across the different components managing an electrical grid, from field processes to market exchanges, allowing the information flowing more and more freely across applications and domains and creating opportunity for new applications that are not any more constraint to a single domain. 1. Introduction The electrical grid undergoes a fundamental change with the introduction of the Smart Grid. Installation of end consumer smart meters, deployment of distributed renewable energy generation, and interconnection of operation and information systems require new solutions that can intelligently monitor and manage the infrastructure. The Smart Grid aims on raising operational efficiencies of operators by increasing the flow of information and automation in order to enable better and faster decisions, hence reducing operational cost. In order to achieve this, utilities are facing some challenges to improve the power delivery methods and utilization, including the integration of control room systems for better workflow, new consumer demands, and security of supply. Additionally, future trends and developments in operations centers, for example, Supervisory Control and Data Acquisition (SCADA) systems, can be observed.(i)Integration of operations’ centers for smart distribution grids includes the advanced integration of existing IT infrastructure as well as the development of new applications.(ii)SCADA systems are becoming increasingly ubiquitous. Thin clients, web portals, and web based products are gaining popularity with most major vendors but also introduce additional security aspects.(iii)SCADA systems become more integrated and connected with existing Enterprise Resource Planning (ERP) systems and other non-SCADA or external applications but require new, tailored architectural approaches to guarantee continuous operation of critical resources.(iv)Information Technology (IT) and
The Smart Grids in China—A Review  [PDF]
Yanshan Yu,Jin Yang,Bin Chen
Energies , 2012, DOI: 10.3390/en5051321
Abstract: The concept of the smart grid has been gaining more and more attention worldwide since it was proposed by the U.S. Electric Power Research Institute in 2001. Recently, it has been propelled again by the promotion of low carbon economies in developing countries. To satisfy the exponential increase in electricity demand and alleviate environmental degradation caused by fossil fuel-based power generation, China has made great efforts in constructing a smart grid as a substitution of traditional energy-intensive power grid. In the 12th Five-Year Plan in particular, it was stated that emphasis should be placed on the development of renewable energy and smart grids. The objective of this paper is to provide an insight into the current research on smart grids, and shed light on the development of smart grids in China, based on the analysis of which, the obstacles and barriers in the development process are identified. Finally, policy prospects on the construction of smart grids in China are proposed from the aspects of technology, administration and management.
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